The overarching goal of this project is to better understand the ways in which cognitive and emotional self-regulation are disrupted in depression. When faced with unfavorable situations, people with depression are unable to implement adaptive behavior change. Self-regulatory deficits in depression extend to both cognitive and emotional domains, influencing the ability to recover from mistakes in cognitive performance tasks as well as the ability to cope adequately with life stressors. The proposed research aims to quantify self-regulatory deficits in the laboratory, confirming that depressed people do not recover well from mistakes in performance tasks. Further, the research tests the hypothesis that exaggerated cortical arousal following mistakes can account for poor post-error performance deficits in depression. Cortical arousal will be measured by quantifying EEG power spectrum changes immediately following the detection of a performance mistake. Finally, the proposed research will test the hypothesis that cognitive self-regulatory deficits predict poor coping with daily stressors, as measured through a daily experience sampling protocol. That is, depression-related deficits in post-error performance regulation and post-error cortical arousal are expected to predict increased negative affect and poor coping behaviors following daily stressors. This research aims to demonstrate that deficits in cognitive control and maladaptive emotional reactions to stress arise from the same fundamental difficulty in self-regulatory control in people with depression. PUBLIC HEALTH RELEVANCE: Depression is one of the most prevalent, disabling, and persistent mental illnesses. The proposed research aims to identify common self-regulatory deficits that result in poor cognitive performance and poor coping with daily stressors in depression. By understanding factors that contribute to a persistent cycle of failure in depression, such research may ultimately yield avenues for fruitful intervention.